Virtual image display apparatus and video device unit manufacturing method

ABSTRACT

An image display device is a self-luminous type device including a light emitting portion, and a casing portion of a display device unit has a heat dissipating structure portion through which a part of the image display device is exposed for heat dissipation. In manufacturing the display device unit, when performing simple and reliable assembly while securing a high heat dissipation characteristic, for example, by using characteristics of a silicon substrate, high accurate positioning is performed in a display device positioning portion.

This application is a continuation application of U.S. patentapplication Ser. No. 16/299,504, filed on Mar. 12, 2019, which in turnis a divisional application of U.S. patent application Ser. No.15/419,432, filed on Jan. 30, 2017, which claims priority to JP2016-192990, filed Sep. 30, 2016, and JP 2016-025615, also filed Feb.15, 2016. The disclosures of each of the above are hereby incorporatedby reference in their entireties.

BACKGROUND 1. Technical Field

The present invention relates to a virtual image display apparatus and avideo device unit manufacturing method that presents a video formed byan image display device or the like to an observer.

2. Related Art

As a virtual image display apparatus such as a head-mounted display(hereinafter, referred to as an HMD) which is mounted in a head portionof an observer, a device in which a liquid crystal display panel isapplied to an image display device (video device) or the like is known(for example, JP-A-2014-191013, or the like). In a case where imageformation is performed using the liquid crystal display panel, it isnecessary that a light source such as a backlight is separately providedand a space for accommodating the light source is provided. In order torealize miniaturization in such a situation, a device having a structurethat the liquid crystal display panel is pinched between two casings isknown (see JP-A-2014-191013).

On the other hand, in order to satisfy a demand for furtherminiaturization, a technique that employs a self-luminous type videodevice in which a separate light source is not necessary may beconsidered.

However, for example, since a self-luminous type video device such as anorganic EL (OLED) panel has a structure in which a light emitting sourceis provided in a panel substrate and a driver IC for driving, a powersource element, or the like is provided therein, internal temperatureeasily rises. Particularly, in the case of such an organic EL, it isconsidered that performance degradation or life shortening becomesnoticeable due to increase in internal temperature as characteristicsthereof.

SUMMARY

An advantage of some aspects of the invention is to provide a virtualimage display apparatus and a video device unit manufacturing methodcapable of achieving weight reduction and miniaturization of an overalldevice using a self-luminous type video device, maintaining performanceof the video device, and forming an excellent image.

A virtual image display apparatus according to a first aspect of theinvention includes: a video device that includes a light emittingportion that generates video light; and a casing portion thataccommodates the video device, in which the casing portion has a heatdissipating structure portion through which a side of the video deviceopposite to a side thereof where video light is emitted is exposed forheat dissipation.

In the virtual image display apparatus, since the virtual image displayapparatus is a self-luminous type device that includes a light emittingportion for generating video light in a video device and does not need aseparate light source, it is possible to achieve weight reduction andminiaturization of the video device, and to achieve weight reduction andminiaturization of the entirety of the virtual image display apparatus.Further, since the casing portion has the heat dissipating structureportion through which a part of the video device is exposed for heatdissipation, it is possible to reduce increase in internal temperatureof the video device. Furthermore, although the video device is aself-luminous type, it is possible to avoid performance degradation orlife shortening due to increase in internal temperature, and to achieveexcellent image formation.

A video display unit according to a first aspect of the inventionincludes: a video device that includes a light emitting portion thatgenerates video light; and a casing portion that accommodates the videodevice, in which the casing portion has a heat dissipating structureportion through which a side of the video device opposite to a sidethereof where video light is emitted is exposed for heat dissipation anda video device positioning portion that determines an accommodationposition of the video device by being in contact with a place other thana place where the video device is exposed.

In the video device unit, since the video device unit is a self-luminoustype device that includes a light emitting portion for generating videolight in a video device and does not need a separate light source, it ispossible to achieve weight reduction and miniaturization of the videodevice, and to achieve weight reduction and miniaturization of the videodevice unit. Further, since the casing portion has the heat dissipatingstructure portion through which a part of the video device is exposedfor heat dissipation, it is possible to reduce increase in internaltemperature of the video device. Furthermore, although the video deviceis a self-luminous type, it is possible to avoid performance degradationor life shortening due to increase in internal temperature, and toachieve excellent image formation.

A video device unit manufacturing method according to a first aspect ofthe invention is a manufacturing method of a video device unit includinga video device that includes a light emitting portion that generatesvideo light and a casing portion that accommodates the video device, inwhich the casing portion includes a heat dissipating structure portionthrough which a side of the video device opposite to a side thereofwhere video light is emitted is exposed for heat dissipation and a videodevice positioning portion that is in contact with a place other than aplace where the video device is exposed and determines an accommodationposition of the video device. The method includes: applying an adhesivefor fixing the video device in the video device positioning portion ofthe casing portion; and positioning the video device and the casingportion and fixing the video device and the casing portion using theadhesive with the video device being exposed through the heatdissipating structure portion.

In the video device unit manufacturing method, in manufacturing aself-luminous type video device unit capable of achieving excellentimage formation by avoiding performance degradation or life shorteningdue to increase in internal temperature while achieving weight reductionand miniaturization, it is possible to achieve simple and reliableassembly while securing a high heat dissipation characteristic in a heatdissipating structure portion.

A virtual image display apparatus according to a second aspect of theinvention includes: a video device that includes a light emittingportion that generates video light; and a casing portion thataccommodates the video device, in which the casing portion has a thermalconductive member that conducts heat of the light emitting portion incontact with the video device.

In the virtual image display apparatus, since the virtual image displayapparatus is a self-luminous type device that includes a light emittingportion for generating video light in a video device and does not need aseparate light source, it is possible to achieve weight reduction andminiaturization of the video device, and to achieve weight reduction andminiaturization of the entirety of the virtual image display apparatus.Further, since the casing portion has the thermal conductive member thatconducts heat of the light emitting portion in contact with the videodevice for heat dissipation, it is possible to reduce increase ininternal temperature of the video device. Furthermore, although thevideo device is a self-luminous type, it is possible to avoidperformance degradation or life shortening due to increase in internaltemperature, and to achieve excellent image formation.

A video device unit according to a second aspect of the inventionincludes: a video device that includes a light emitting portion thatgenerates video light; and a casing portion that accommodates the videodevice, in which the casing portion has a thermal conductive member thatconducts heat of the light emitting portion in contact with the videodevice.

In the video device unit, since the virtual image display apparatus is aself-luminous type device that includes a light emitting portion forgenerating video light in a video device and does not need a separatelight source, it is possible to achieve weight reduction andminiaturization of the video device, and to achieve weight reduction andminiaturization of the entirety of the virtual image display apparatus.Further, since the casing portion has the thermal conductive member thatconducts heat of the light emitting portion in contact with the videodevice for heat dissipation, it is possible to reduce increase ininternal temperature of the video device. Furthermore, although thevideo device is a self-luminous type, it is possible to avoidperformance degradation or life shortening due to increase in internaltemperature, and to achieve excellent image formation.

A video device unit manufacturing method according to a second aspect ofthe invention is a manufacturing method of a video device unit includinga video device that includes a light emitting portion that generatesvideo light and a casing portion that accommodates the video device, inwhich the casing portion has a thermal conductive member that conductsheat of the light emitting portion in contact with the video device. Themethod includes: applying an adhesive for fixing the video device in acontact place with the video device of the thermal conductive member;and positioning the video device and the casing portion and fixing thevideo device and the casing portion using the adhesive with the videodevice being exposed through the heat dissipating structure portion.

In the video device unit manufacturing method, in manufacturing aself-luminous type video device unit capable of achieving excellentimage formation by avoiding performance degradation or life shorteningdue to increase in internal temperature while achieving weight reductionand miniaturization, it is possible to achieve simple and reliableassembly while securing a high heat dissipation characteristic in athermal conductive member that forms a casing portion.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to the accompanyingdrawings, wherein like numbers reference like elements.

FIG. 1 is a perspective view illustrating an appearance of an example ofa virtual image display apparatus according to a first embodiment.

FIG. 2 is a diagram conceptually illustrating an optical path of videolight.

FIG. 3 is a diagram illustrating retention of an optical system(projection lens) by a lens barrel.

FIG. 4 is a perspective view illustrating a state where a display deviceunit is assembled in a projection lens.

FIG. 5 is a perspective view illustrating a state of a structure of adisplay portion of a virtual image display apparatus.

FIG. 6A is a perspective view illustrating an appearance of a displaydevice unit, and FIG. 6B is a perspective view illustrating a state ofthe display device unit in FIG. 6A when seen from a different angle.

FIG. 7A is a front view of a display device unit, FIG. 7B is a side viewthereof, and FIG. 7C is a rear view thereof.

FIG. 8A is a sectional side view of a display device unit, and FIG. 8Bis a sectional side view of a casing portion.

FIGS. 9A and 9B are diagrams illustrating a positioning reference inassembly of a display device unit.

FIGS. 10A to 10E are diagrams illustrating an example of a manufacturingprocess of a display device unit.

FIG. 11A is a conceptual diagram illustrating a modification example ofa positioning structure inside a display device unit, and FIG. 11B is aconceptual diagram illustrating another modification example of thepositioning structure inside the display device unit.

FIG. 12A is a conceptual diagram illustrating still another modificationexample of the display device unit, and FIG. 12B is a cross-sectionalview taken along an arrow line in FIG. 12A.

FIG. 13A is a perspective view of a display device unit assembled in avirtual image display apparatus according to a second embodiment, FIG.13B is another perspective view thereof, and FIG. 13C is a sectionalside view thereof.

FIG. 14A is a perspective view of an image display device assembled in adisplay device unit, and FIG. 14B is a side view thereof.

FIGS. 15A to 15E are diagrams illustrating an example of a manufacturingprocess of a display device unit and an assembly process of the displaydevice unit and a lens barrel.

FIG. 16 is a perspective view illustrating an example of a displaydevice unit assembled in a virtual image display apparatus according toa third embodiment.

FIG. 17A is a perspective view illustrating a state where a displaydevice unit is assembled in a lens barrel built in a virtual imagedisplay apparatus according to a fourth embodiment, FIG. 17B is a frontview thereof, and FIG. 17C is a side view thereof.

FIG. 18A is a perspective view illustrating a display device unit of amodification example, and FIG. 18B is a rear view thereof.

FIG. 19 is a conceptual diagram illustrating another modificationexample of the virtual image display apparatus.

FIG. 20 is a diagram illustrating still another modification example ofthe virtual image display apparatus.

FIG. 21A is a conceptual plan view illustrating still anothermodification example of the virtual image display apparatus, and FIG.21B is a side view thereof.

FIG. 22 is a conceptual plan view illustrating still anothermodification example of the virtual image display apparatus.

DESCRIPTION OF EXEMPLARY EMBODIMENTS First Embodiment

Hereinafter, an embodiment of a virtual image display apparatus in whicha display device unit which is a video device unit according to a firstembodiment of the invention is provided will be described in detail withreference to FIG. 1.

As shown in FIG. 1, a virtual image display apparatus 100 according tothis embodiment is a head-mounted display (HMD) having an appearancesuch as glasses, and may cause an observer or a user who wears thevirtual image display apparatus 100 to view image light (video light)based on a virtual image, and may cause the observer to view or observean external world image in a see-through manner. The virtual imagedisplay apparatus 100 includes a first display device 100A, a seconddisplay device 100B, and a frame portion 102.

The first display device 100A and the second display device 100B areportions that form virtual images for the right eye and the left eye,respectively, and include first and second optical members 101 a and 101b that cover front sides of the observer's eyes in a see-through manner,and first and second image formation main portions 105 a and 105 b,respectively. As will be described later, each of the first and secondimage formation main portions 105 a and 105 b is configured by anoptical system for image formation including a display device (videodevice), a projection lens, and the like, a member that accommodates theoptical system, and the like. The display device (video device), theprojection lens, and the like are supported and accommodated by beingcovered by a cover-shaped exterior member 105 d. The first and secondoptical members 101 a and 101 b are light guide portions that guidevideo light formed by the first and second image formation main portions105 a and 105 b and overlap external world light and video light to beviewed, and form a light guide device. Hereinafter, the first opticalmember 101 a or the second optical member 101 b is referred to as alight guide device 20. The first display device 100A and the seconddisplay device 100B individually function as a virtual image displayapparatus.

The frame portion 102 is a metallic integral part made of an elongatedmember bent in a U-shape in a plan view. Here, as an example, the frameportion 102 is formed of a magnesium alloy. In other words, the frameportion 102 is configured so that a magnesium frame which is a metallicintegral part is a main body portion 102 p. Further, the frame portion102 includes a central portion 102 a having a thick structure providedto be connected to both of the first optical member 101 a and the secondoptical member 101 b (light guide devices 20 which are a pair of lightguide portions), and a support body 102 b that extends along the firstand second optical members 101 a and 101 b from the central portion 102a and forms a portion that is bent in a U-shape.

The central portion 102 a is pinched between tip end sides of the firstand second optical members 101 a and 101 b, to thereby fix relativepositions thereof. In addition, the support body 102 b forms first andsecond peripheral portions 102 c and 102 d which are portions bent in aU-shape, are connected (assembled) to the first and second opticalmembers 101 a and 101 b in the first and second peripheral portions 102c and 102 d, to strengthen the fixing.

Temples 104 which are string portions that extend backward from rightand left ends of the frame portion 102 are provided, and may besupported being in contact with the observer's ears, temples or thelike. Further, the first and second image formation body portions 105 aand 105 b may be added as parts of the temples 104 from the frameportion 102.

Hereinafter, an example of a structure for performing light guiding ofvideo light, and the like in the virtual image display apparatus 100will be conceptually described with reference to FIG. 2 and the like.Devices for performing light guiding of video light are the firstdisplay device 100A and the second display device 100B (see FIG. 1, orthe like) as described above, but since the first display device 100Aand the second display device 100B have symmetrically the samestructures, only the first display device 100A will be described, anddescription of the second display device 100B will not be repeated. Asshown in FIG. 2, the first display device 100A includes an image displaydevice 80 that forms video light, a projection lens 30 for imaging whichis accommodated in a lens barrel, and the light guide device 20 (thefirst optical member 101 a) that guides video light passed through theimage display device 80 and the projection lens 30. The light guidedevice 20 is configured by a light guide member 10 for light guiding andsee-through, and a light transmitting member 50 for see-through.

The image display device 80 may be formed as a video device (videodisplay device) which is configured by a self-luminous type device suchas an organic EL. Further, for example, in addition to the video displaydevice (video device) which is a transmission-type spatial lightmodulator, the image display device 80 may be configured to include alighting system (not shown) which is a backlight that emits illuminationlight to the video display device and a drive controller (not shown)that controls an operation thereof. In this embodiment, the imagedisplay device 80 which is the video device is configured to beaccommodated in a casing portion to be unitized (modularized), and thus,alignment to the projection lens 30 is performed. Furthermore, aconfiguration in which the image display device (video device) 80 isaccommodated in the casing portion to be unitized (modularized) isreferred to as a display device unit (or video device unit).

The projection lens 30 is a projection optical system that includesplural (for example, three) optical elements (lenses) disposed along anincident-side optical axis AX as components, for example, in which theoptical elements are accommodated and supported by a lens barrel 39 asshown in FIG. 3. Each optical element is configured by an asphericalsurface lens including both of an aspherical surface which is notaxisymmetric (non-axisymmetric aspherical surface) and an asphericalsurface which is axisymmetric (axisymmetric aspherical surface), forexample, so as to form an intermediate image corresponding to a displayimage in the light guide member 10 in cooperation with a part of thelight guide member 10 that forms the light guide device 20. Theprojection lens 30 projects video light formed by the image displaydevice 80 toward the light guide device 20 to be incident thereon.

The light guide device 20 is configured by the light guide member 10 forlight guiding and see-through, and the light transmitting member 50 forsee-through as described above. The light guide member 10 is a part ofthe light guide device 20 of a prism type and is an integrated member,but as shown in FIG. 2, may be divided into a first light guide portion11 on a light emitting side and a second light guide portion 12 on alight incident side. The light transmitting member 50 is a member thatassists the see-through function of the light guide member 10 (auxiliaryoptical block), and is integrally fixed to the light guide member 10 toform one light guide device 20. The light guide device 20 is screwed tothe lens barrel 39 (see FIG. 3 or the like), for example, and ispositioned and fixed to the projection lens 30 with high accuracy. Asshown in FIG. 3, a part which is integrally unitized by attaching theprojection lens 30 and the light guide device 20 to the lens barrel 39is referred to as an optical display unit LU.

Returning to FIG. 2, the light guide member 10 includes first to fifthsurfaces S11 to S15 as side surfaces having optical functions. Here, thefirst surface S11 and the fourth surface S14 are continuously adjacentto each other, and the third surface S13 and the fifth surface S15 arecontinuously adjacent to each other. In addition, the second surface S12is disposed between the first surface S11 and the third surface S13. Ahalf mirror layer is collaterally provided on the front surface of thesecond surface S12. The half mirror layer is a reflecting film (that is,semi-transmission type reflecting film) having a light transmittingproperty, and is formed by forming a metallic reflecting film or adielectric multilayer film, in which a reflectance with respect to videolight is appropriately set.

Hereinafter, an optical path of video light (here, referred to as videolight GL) will be schematically described with reference to FIG. 2. Thelight guide member 10 causes the video light GL to be incident from theprojection lens 30, and guides the video light GL toward the eyes of anobserver through reflection or the like on the first to fifth surfacesS11 to S15. Specifically, the video light GL from the projection lens 30is first incident to the fourth surface S14 and then is reflected fromthe fifth surface S15, is again incident to the fourth surface S14 fromthe inside and then is totally reflected, is incident to the thirdsurface S13 and then is totally reflected, and then, is incident to thefirst surface S11 and then is totally reflected. The video light GLwhich is totally reflected from the first surface S11 is incident to thesecond surface S12, is partially reflected while partially passingthrough the half mirror layer provided on the second surface S12, and isagain incident to the first surface S11 and passes through the firstsurface S11. The video light GL passed through the first surface S11 isincident to the eyes of an observer or an equivalent position thereof assubstantially parallel light beams. In other words, the observer comesto observe an image using video light which is a virtual image.

As described above, the light transmitting member 50 is integrally fixedto the light guide member 10 to form one light guide device 20, and is amember (auxiliary optical block) that assists the see-through functionof the light guide member 10. The light transmitting member 50 includesa first light transmitting surface S51, a second light transmittingsurface S52, and a third light transmitting surface S53 as side surfaceshaving optical functions. The second light transmitting surface S52 isdisposed between the first light transmitting surface S51 and the thirdlight transmitting surface S53. The first light transmitting surface S51is disposed on a surface that extends from the first surface S11 of thelight guide member 10, the second light transmitting surface S52 is acurved surface which is bonded to the second surface S12 to beintegrated therewith, and the third light transmitting surface S53 isdisposed on a surface that extends from the third surface S13 of thelight guide member 10.

As described above, the light guide device 20 causes an observer to viewvideo light using the light guide member 10 and causes the observer toan external world image having a small amount of distortion usingcooperation of the light guide member 10 and the light transmittingmember 50. In other words, light which is incident to a +X side withreference to the second surface S12 of the light guide member 10, inexternal world light as component light that forms an external worldimage to be viewed, passes through the third surface S13 and the firstsurface S11 of the first light guide portion 11, but at this time, sincethe third surface S13 and the first surface S11 are formed in planeswhich are approximately parallel to each other (diopter is approximatelyzero), aberration or the like hardly occurs. Further, light which isincident to a −X side with reference to the second surface S12 of thelight guide member 10, in the external light, in other words, lightwhich is incident to the light transmitting member 50 passes through thethird light transmitting surface S53 and the first light transmittingsurface S51 provided therein, but at this time, since the third lighttransmitting surface S53 and the first light transmitting surface S51are formed in planes which are approximately parallel to each other,aberration or the like hardly occurs. Furthermore, when light which isincident to the light transmitting member 50 corresponding to the secondsurface S12 of the light guide member 10, in external world light,passes through the third transmitting surface S53 and the first surfaceS11, since the third transmitting surface S53 and the first surface S11are formed in planes which are approximately parallel to each other,aberration or the like hardly occurs. With such a configuration, anobserver observes an external world image without distortion through thelight transmitting member 50.

The above-described configuration is similarly applied to the seconddisplay device 100B (see FIG. 1 or the like). Thus, it is possible toform images corresponding to the right and left eyes, respectively.

Hereinafter, a display device unit DU which is a video device unitincluding the image display device (video device) 80 will be describedwith reference to FIG. 4, and the like. FIG. 4 is a perspective viewillustrating a state where the display device unit DU is assembled inthe projection lens 30 (lens barrel 39). In the first display device100A and the second display device 100B, since the display device unitDU is symmetric and has the same structure, in FIGS. 4 and 5, only thedisplay device unit DU on the left side is shown for description, anddescription of the display device unit DU on the right side will not berepeated.

As shown in FIG. 4, the display device unit DU has a configuration inwhich the image display device (video device) 80 is accommodated in acasing portion 88 to be unitized (modularized). In other words, theimage display device 80 is accommodated in the box-shaped casing portion88 through fitting, and is retained so as not to move. Particularly, inthis embodiment, as shown in the figure, the casing portion 88 isprovided with a heat dissipating structure portion 88 a, and thus,supports and fixes the image display device 80 in a state where a sideof the image display device 80 opposite to a side thereof where videolight is emitted is opened and exposed. Furthermore, in this embodiment,as shown in FIG. 5, by providing a heat dissipating portion DPconfigured so that a thermal conductive tape is directly attached to aportion exposed from the casing portion 88 in a rear side portion of theimage display device 80, for example, heat dissipation of the imagedisplay device 80 is promoted. In this example, the heat dissipatingportion DP formed by the thermal conductive tape is attached to extendover a frame portion 102 which is a support frame from the image displaydevice 80 to the lens barrel 39.

Here, in a case where the above-described self-luminous type imagedisplay device (video device) 80 is applied to an HMD to form a highluminance image, a structure in which a light emitting source isprovided in a panel substrate and a driver IC for driving, a powersource element, and the like is provided therein is used. Thus, increasein internal temperature may cause a problem. Particularly, in a casewhere an organic EL (OLED) panel is applied to a panel portion of theimage display device (video device) 80 as in this embodiment, there is aconcern that performance deterioration or life shortening due toincrease in internal temperature becomes noticeable as itscharacteristic.

In this embodiment, in order to solve the above-mentioned problem, in astructure of the display device unit (video device unit) DU,particularly, by exposing a part of a silicon substrate SS that formsthe image display device 80 through the heat dissipating structureportion 88 a of the casing portion 88, it is possible to efficientlyperform heat dissipation using the heat dissipating portion DP (see FIG.5) configured by a thermal conductive tape or the like, and to provide astructure in which accuracy of an assembly position of the casingportion 88 and the image display device 80 is enhanced using edgesurfaces of the silicon substrate SS of the image display device 80.

Hereinafter, a structure of the display device unit (video device unit)DU or the casing portion 88 and the image display device 80 that formthe display device unit DU will be described in detail with reference toFIGS. 6A and 6B, and the like.

First, a structure of the image display device 80 among the imagedisplay device 80 and the casing portion 88 that form the display deviceunit DU will be described with reference to FIGS. 6A and 6B, FIGS. 7A to7C, and FIGS. 8A and 8B. As shown in the figures, the image displaydevice 80 includes a main body portion 80 a of a rectangular plate shapeaccommodated in the casing portion 88, and a flexible printed circuit(FPC) portion 80 f that is connected and extended from the main bodyportion 80 a. Here, as shown in FIG. 8A, the main body portion 80 aincludes a silicon substrate SS on which various circuits are provided,which forms an appearance of the main body portion 80 a, a lightemitting portion 80 k that is an organic EL element including an organicEL material and generates color light to become video light, and aprotective glass GG for sealing that blocks the light emitting portion80 k in cooperation with the silicon substrate SS. The image displaydevice 80 performs a light emitting operation according to a drivesignal received from the FPC portion 80 f, to thereby emit video lighttoward the protective glass GG, that is, in a +z direction. Furthermore,as shown in the figure, the image display device 80 is accommodated inthe casing portion 88 in a state where a part of the main body portion80 a is exposed, as described above. More specifically, the imagedisplay device 80 is supported and fixed in a state where the entiretyof a rear surface SSr of the silicon substrate SS disposed on a sideopposite to a side where video light is emitted is exposed.

Here, in this embodiment, with respect to a configuration of the imagedisplay device 80, a silicon (Si) substrate is employed as aself-luminous type element substrate on which an organic EL (OLED) ismounted. Thus, first, it is possible to provide high thermalconductivity with respect to the above-described heat dissipation, andto perform highly efficient heat dissipation. Further, in manufacturingof a circuit board for forming a light emitting element, it is possibleto form a circuit having a precise configuration, that is, a finestructure (for example, in the unit of several microns). Furthermore, asthe silicon substrate is configured to form the appearance of the imagedisplay device 80, each edge surface of the silicon substrate is cutwith high accuracy using the height of accuracy (for example, withinseveral tens of microns in manufacturing error) in silicon dicing to beused for positioning when the image display device 80 is accommodated inthe casing portion 88, and thus, it is possible to set the positioningaccuracy with respect to the casing portion 88 to become higher accuracy(for example, compared with that of a surface or the like of theprotective glass GG). In addition, as described later, the casingportion 88 also serves as a member for aligning the display device unit(video device unit) DU in which the image display device 80 is providedand another optical member (in this embodiment, the lens barrel thataccommodates the projection lens 30), but by maintaining the height ofaccuracy inside the unit, as a result, it is possible to maintain thepositioning accuracy of the image display device 80 with respect to theprojection lens 30 in a high accuracy state. That is, in this case,using the accuracy of dicing in formation of the edge surfaces of thesilicon substrate, it is possible to achieve positioning with highaccuracy, to reduce an adjustment range in assembly of the image displaydevice 80 with respect to another member, and to achieve miniaturizationin the entire device.

Next, a structure of the casing portion 88 among the image displaydevice 80 and the casing portion 88 that form the display device unit DUwill be described. As shown in the figure (for example, FIG. 8B), thecasing portion 88 has a frame body structure having a through hole in acentral portion, and includes a heat dissipating structure portion 88 athat is formed with an opening OP through which a part of the imagedisplay device 80 is exposed, a display device positioning portion(video device positioning portion) 88 b that performs positioning andfixing of the image display device 80, a mask portion 88 m that isprovided on a side where video light is emitted, which is opposite tothe heat dissipating structure portion 88 a or the display devicepositioning portion 88 b, and removes unnecessary light from componentlight emitted from the image display device 80, and protrusion members(fitting portions) 88 u and 88 v which are attachment portions forperforming attachment alignment with respect to the lens barrel 39 (seeFIG. 4, or the like). That is, the casing portion 88 has a mask functionfor blocking unnecessary light and an alignment function in mountingwith respect to other optical parts. The casing portion 88 is made of ametallic member with high thermal conductivity, such as aluminum ormagnesium, for example, has a single member configuration formed bydie-casting or the like, for example, that is, is a structure configuredby a single member. In this case, by forming the casing portion 88 tohave the single member configuration in which the opening OP is providedso that heat dissipation of the image display device 80 is secured, itis possible to achieve simple miniaturization of the image displaydevice 80 and peripheral configurations thereof while maintainingnecessary functions.

For example, as shown in FIG. 7C or FIG. 8B, in the casing portions 88,the heat dissipating structure portion 88 a is formed as a grooveportion of a U shape which is opened on a rear surface side thereof (aside opposite to a side where video light is emitted), that is, in a +ydirection on a −z side in the figure, and the main body portion 80 a ofthe image display device 80 is inserted from the +y side. Further, asdescribed above, the casing portion 88 has a frame body structure havinga through hole in a central portion, and the heat dissipating structureportion 88 a is formed with the opening OP together with the U-shapedgroove portion. In other words, as shown in the respective drawingsother than FIG. 8B, the entirety of the rear surface SSr of the siliconsubstrate SS is exposed by the opening OP. From the standpoint of thecasing portion 88, the casing portion 88 has the heat dissipatingstructure portion 88 a that causes the rear surface SSr to be exposedthrough the opening OP for heat dissipation, and thus, the rear surfaceSSr of the silicon substrate SS serves as an exposure portion throughthe heat dissipating structure portion 88 a.

Further, in the casing portion 88, the display device positioningportion (video device positioning portion) 88 b that performspositioning by contact with the image display device 80 is configured bya first reference surface SF1 which is a reference plane portion forpositioning in the z direction, a second reference surface SF2 which isa reference plane portion for positioning in the x direction, and athird reference surface SF3 which is a reference plane portion forpositioning in the y direction, as shown in the figure. All thereference surfaces SF1 to SF3 come into contact with the respective edgesurfaces SS1 to SS3 other than the rear surface SSr among the edgesurfaces of the silicon substrate SS of a rectangular plate shape, forexample, as shown in FIGS. 9A and 9B, to thereby perform positioningwith high accuracy.

As described above, the casing portion 88 is a member that forms thedisplay device unit DU that supports and fixes the image display device80 while positioning by fitting and accumulates the image display device80 to be unitized (modularized) and forms an alignment portion forperforming assembly of the image display device 80, that is, the displaydevice unit DU with respect to the lens barrel 39.

Further, in the casing portion 88, a pair of protrusion members 88 u and88 v that extends in parallel with the optical axis AX is formed on the+z side (side where video light is emitted). As shown in FIG. 4 or FIG.5, for example, the protrusion members (fitting portions) 88 u and 88 vare fitting portions that are smoothly fitted to a rear end portion ofthe lens barrel 39 of the projection lens (projection optical system) 30so that the rear end portion is pinched therebetween, and are used tofix the casing portion 88 to the lens barrel 39. In other words, in FIG.4, or the like, an adhesive fills a space between the inner surfaces ofthe protrusion members (fitting portions) 88 u and 88 v and a sidesurface of the lens barrel 39. The adhesive is cured after alignment ofthe casing portion 88 with respect to the lens barrel 39, so that thecasing portion 88 is fixed to the lens barrel 39. Here, it is possibleto perform alignment relating to rotating shafts in three directions inaddition to three directions of an up-down direction, a right-leftdirection, and a front-rear direction. At a previous stage of thealignment, in the light guide member 10 of the light guide device 20, abase side thereof is be fitted to the lens barrel 39 to be fixedthereto. In this state, the casing portion 88 that accommodates theimage display device 80 as described above aligns with the lens barrel39 assembled with the light guide member 10 and the like, so thatpositioning of a final image can be performed. Particularly, in the caseof a right-left pair configuration as in this embodiment, it isnecessary to perform adjustment in the unit of pixels so that an imagefor the right eye side and an image for the left side eye are viewed ina state of being overlapped, and the positioning becomes very important.On the other hand, in this embodiment, since the image display device 80is fitted to the casing portion 88 with high accuracy, it is possible tominimize a margin for the adjustment, and to avoid increase in size ofthe device as much as possible while enabling positional adjustment.

Hereinafter, an example of a manufacturing process of the display deviceunit DU, which is also a process of a manufacturing process of thevirtual image display apparatus 100, will be described with reference toFIGS. 10A to 10E.

First, as shown in FIG. 10A, in the casing portion 88 which is a framebody structure, an adhesive 88 s is applied on a surface including thefirst reference surface SF1 that is a reference for positioning in the zdirection or a margin surface NS which is a surface adjacent to thefirst reference surface SF1 (adhesive applying process). Here, forexample, a place where a drive circuit or the like is disposed may beused as a part of the margin surface NS for adhesion. In the firstreference surface SF1, a configuration in which an end surface of theimage display device 80 (silicon substrate SS) directly comes intocontact with the first reference surface SF1 without through theadhesive 88 s may be used. Further, for example, it may be consideredthat a high thermal conductive silicon-based adhesive or a thermalconductive epoxy adhesive is used as the adhesive 88 s. By using such ahigh thermal conductive adhesive, it is possible to enhance heatdissipation even on a side where video light is emitted.

Next, as shown in FIG. 10B, by dropping the image display device 80 ontothe surface of the first reference surface SF1, positioning is performedon the first reference surface SF1 while pushing the adhesive 88 s. Thatis, an edge surface SS1 of the image display device 80 (siliconsubstrate SS) is brought into contact with the first reference surfaceSF1 to perform positioning (corresponding to FIG. 9A) in the z direction(first positioning process). Here, in the x direction, there is almostno margin (for example, a margin within several tens of microns, whichis a level of errors in dicing of silicon), and thus, positioningrelating to the second reference surface SF2. That is, an edge surfaceSS2 of the image display device 80 (silicon substrate SS) comes intocontact with the second reference surface SF2 to perform positioning inthe x direction (second positioning process).

Then, as shown in FIG. 10C, by pushing the image display device 80 inthe −y direction (arrow Y1 direction) using a rod-shaped jig JG, an edgesurface SS3 of the image display device 80 (silicon substrate SS) comesinto contact with (strikes) the third reference surface SF3, and thus,positioning in the y direction (corresponding to FIG. 9B) is performed(third positioning process). Through the above-described first to thirdpositioning processes, the first to third reference surfaces SF1 to SF3are fixed by the adhesive 88 s in a state where the rear surface SSr ofthe image display device 80 is exposed, to thereby function as thedisplay device positioning device (video device positioning portion) 88b that determines an accommodation position of the image display device80 in the casing portion 88. In the adjustment due to the jig JG shownin FIGS. 10B to 10C, that is, in slide movement, it is possible toprevent the adhesive 88 s from being attached to a rectangular displayarea EA indicated by a broken line in the figure (that is, an area wherean organic EL element or the like is to be formed and video light is tobe emitted).

After the first to third positioning processes, as shown in FIG. 10D,the positional relationship between the image display device 80 and thecasing portion 88 is fixed so as not to move by a hook jig FG capable ofbeing inserted in the x direction, and then, the adhesive 88 s is cured.Finally, after the adhesive 88 s is cured, by separating the hook jigFG, as shown in FIG. 10E, the display device unit DU in which the imagedisplay device 80 is accommodated in the casing portion 88 to beunitized is manufactured. The cured adhesive 88 s becomes an adhesiveportion BP that fixes the image display device 80 and the casing portion88.

As described above, since the virtual image display apparatus 100including the display device unit DU according to this embodiment is aself-luminous type device that includes the light emitting portion 80 kfor generating video light in the image display device 80 which is avideo device and does not need a separate light source, it is possibleto achieve weight reduction and miniaturization, and to achieve weightreduction and miniaturization of the entirety of the virtual imagedisplay apparatus 100. Further, since the casing portion 88 of thedisplay device unit DU has the heat dissipating structure portion 88 athrough which a part of the image display device 80 is exposed for heatdissipation, it is possible to reduce increase in internal temperatureof the image display device 80. Further, although the image displaydevice 80 is a self-luminous type, and particularly, includes an organicEL (OLED), it is possible to avoid performance degradation or lifeshortening due to increase in internal temperature, and to achieveexcellent image formation. Furthermore, in manufacturing the displaydevice unit DU, it is possible to perform simple and reliable assemblywhile securing a high heat dissipation characteristic. Here,particularly, it is possible to perform positioning with high accuracyusing the characteristics of the silicon substrate SS.

Hereinafter, a virtual image display apparatus according to amodification example of this embodiment will be described with referenceto FIG. 11A. In the above-described embodiments, the first to thirdreference surfaces SF1 to SF3 that form the display device positioningportion (video device positioning portion) 88 b are all formed in aplane shape, but for example, a part thereof may be formed in aprotrusion shape. For example, in an example shown in FIG. 11A, insteadof a reference plane for positioning in the y direction, third referenceprotrusion portions TP3 and TP3 are provided at the correspondingplaces. In the shown example, the third reference protrusion portionsTP3 and TP3 are provided at two places of both ends of a surfacecorresponding to the plane, to thereby set the third reference surfaceSF3. In this case, an error in positioning in the y direction due topushing in the arrow Y1 direction using a jig or the like can becomezero or can be close to zero by the third reference protrusion portionsTP3 and TP3.

Further, for example, as shown in FIG. 11B, positioning in the xdirection may be performed using a protrusion shape. That is, instead ofa plane which is a positioning reference in the x direction, secondreference protrusion portions TP2 and TP2 are provided at correspondingplaces. In the shown example, the second reference protrusion portionsTP2 and TP2 are provided at two places of both ends of a surface(one-side surface) corresponding to the plane to set the secondreference surface SF2. In this case, an error in positioning in the xdirection and the y direction due to pushing in the arrow X1 directionand the arrow Y1 direction or in a direction including components in thetwo directions using a jig or the like can become zero or can be closeto zero by the second reference protrusion portions TP2 and TP2, and thethird reference protrusion portions TP3 and TP3.

Hereinbefore, the invention has been described with reference to thefirst embodiment, but the present embodiment is not limited to the abovedescription, and may includes various modifications in a range withoutdeparting from the concept of the invention.

For example, in the above example, a structure in which the entirety ofthe rear surface SSr of the silicon substrate SS is in a state of beingexposed by the opening OP is shown, but with respect to exposure of therear surface SSr, it is not essential that the entirety of the rearsurface is exposed as long as heat dissipation or the like issufficient, and a structure in which a part of the rear surface iscovered by another member may be used. For example, as conceptuallyillustrated in FIG. 12A and FIG. 12B corresponding to an AA arrow crosssection of FIG. 12A, a structure in which a pair of contact portions CPthat comes into contact with a part of the rear surface SSr of thesilicon substrate SS is provided in the casing portion 88 to support andfix the silicon substrate SS by the contact portion CP may be used.

Second Embodiment

Hereinafter, a virtual image display apparatus according to a secondembodiment will be described with reference to FIGS. 13A to 13C, and thelike. The virtual image display apparatus according to the secondembodiment is formed by modifying a part of the virtual image displayapparatus in the first embodiment, in which the other configurationsexcept for the structure of the display device unit DU are the same asin the first embodiment. Thus, particularly, with respect to an entireconfiguration thereof, for example, FIGS. 1 to 3 in the first embodimentare applied. The second embodiment is different from the firstembodiment in that a rear surface SSr of a silicon substrate SS iscovered. Accordingly, description of the entire configuration or thelike will not be repeated, and hereinafter, an image display device(video device) 80 or a display device unit DU that is a video deviceunit including the image display device 80 will be described withreference to FIGS. 13A to 13C, and the like. FIG. 13A is a perspectiveview of the display device unit DU (a perspective view including a frontside), FIG. 13B is another perspective view thereof (a perspective viewincluding a rear surface side), and FIG. 13C is a sectional side viewthereof. FIG. 14A is a perspective view of the image display device(video device) 80 assembled in the display device unit DU, and FIG. 14Bis a side view of the image display device 80. In a first display device100A and a second display device 100B, the display device unit DU issymmetric and has the same structure.

As shown in FIGS. 13A to 13C, the display device unit DU has aconfiguration in which the image display device (video device) 80 isaccommodated in a casing portion (casing member) 88 to be unitized(modularized). In other words, the image display device 80 isaccommodated in the box-shaped casing portion 88 through fitting, and isretained so as not to move. Particularly, in this embodiment, as shownin the figures, the casing portion 88 has a plate-shaped portion 88 p orthe like provided being in contact with aside (rear surface side)opposite to a side where video light is emitted in the image displaydevice 80 as a thermal conductive member 88 h, to thereby promote heatdissipation while supporting and fixing the image display device 80. Byfurther providing a heat dissipating portion (see the heat dissipatingportion DP in FIG. 5 described in the first embodiment or FIGS. 21A and21B or the like (to be described later)) configured by directlyattaching a thermal conductive tape made of a graphite sheet or thelike, for example, in a portion of a rear surface of the thermalconductive member 88 h (plate-shaped portion 88 p), heat dissipation ofthe image display device 80 may be promoted.

Here, in a case where the above-described so-called self-luminous typeimage display device (video device) 80 is applied to an HMD to form ahigh luminance image, a structure in which a light emitting source isprovided in a panel substrate and a driver IC for driving, a powersource element, and the like is provided therein may be used. Thus,increase in internal temperature may easily cause a problem.Particularly, in a case where an organic EL (OLED) panel is applied to apanel portion of the image display device (video device) 80 as in thisembodiment, there is a concern that performance deterioration or lifeshortening due to increase in internal temperature becomes noticeable asits characteristic.

In this embodiment, in order to solve the problems, in a structure ofthe display device unit (video device unit) DU, particularly, thethermal conductive member 88 h of the casing portion 88 is configured tobe in contact with the image display device 80 in the form of areacontact, so that efficient heat dissipation can be achieved.Furthermore, a structure in which enhancement of accuracy of an assemblyposition of the casing portion 88 and the image display device 80 isachieved using edge surfaces of the silicon substrate SS of the imagedisplay device 80 is provided.

Hereinafter, details of a structure of the display device unit (videodevice unit) DU or the casing portion 88 and the image display device 80that form the display device unit (video device unit) DU will bedescribed with reference to FIGS. 13A to 13C, and the like.

First, a structure of the image display device 80 among the imagedisplay device 80 and the casing portion 88 that form the display deviceunit DU will be described with reference to FIGS. 13A to 13C, and FIGS.14A and 14B. As shown in the figures, the image display device 80includes a main body portion 80 a of a rectangular plate shapeaccommodated in the casing portion 88, and a flexible printed circuit(FPC) portion 80 f that is connected and extended from the main bodyportion 80 a. Here, as shown in each figure (particularly, as shown inthe sectional side view of FIG. 13C), the main body portion 80 aincludes a silicon substrate SS on which various circuits are provided,which forms an appearance of the main body portion 80 a, a lightemitting portion 80 k that is an organic EL element including an organicEL material and generates color light to become video light, and aprotective glass GG for sealing that blocks the light emitting portion80 k in cooperation with the silicon substrate SS. The image displaydevice 80 performs a light emitting operation according to a drivesignal received from the FPC portion 80 f, to thereby emit the videolight toward the protective glass GG, that is, in the +z direction.

Here, in this embodiment, particularly, in the image display device 80,the entirety of a rear surface SSr (first edge surface SS1) or sidesurfaces (second and third edge surfaces SS2 and SS3) of the siliconsubstrate SS disposed on a side opposite to a side where video light isemitted is fixed to contact surfaces of the casing portion 88 in a stateof being adhered over the entirety of the surfaces by a high thermalconductive adhesion portion BD formed by a high thermal conductiveadhesive such as a high thermal conductive silicon-based adhesive or ahigh thermal conductive epoxy adhesive, for example. In other words, therear surface SSr, or the like becomes a portion (fixed portion) to befixed through contact.

Further, in this embodiment, as described above, with respect to aconfiguration of the image display device 80, a silicon (Si) substrateis employed as a self-luminous type device substrate on which an organicEL (OLED) is mounted. Thus, first, it is possible to provide highthermal conductivity with respect to the above-described heatdissipation, and to perform highly efficient heat dissipation. Further,in manufacturing of a circuit board for forming a light emittingelement, it is possible to form a circuit having a preciseconfiguration, that is, a fine structure (for example, in the unit ofseveral microns). Furthermore, as the silicon substrate is configured toform the appearance of the image display device 80, each edge surface ofthe silicon substrate is cut with high accuracy using the height ofaccuracy (for example, within several tens of microns in manufacturingerror) in silicon dicing to be used for positioning when the imagedisplay device 80 is accommodated in the casing portion 88, and thus, itis possible to set the positioning accuracy with respect to the casingportion 88 with higher accuracy (for example, compared with that of asurface of the protective glass GG, or the like). In addition, thecasing portion 88 also serves as a member for aligning the displaydevice unit (video device unit) DU in which the image display device 80is provided and another optical member (in this embodiment, the lensbarrel 39 that accommodates the projection lens 30, or an opticaldisplay unit LU), but by maintaining the height of accuracy inside theunit, as a result, it is possible to maintain the positioning accuracyof the image display device 80 with respect to the projection lens 30 ina high accuracy state.

Next, a structure of the casing portion 88 among the image displaydevice 80 and the casing portion 88 that form the display device unit DUwill be described. As shown in the FIGS. 13A to 13C, the casing portion88 is a metallic member having high thermal conductivity formed ofaluminum, titanium, copper, stainless steel, a grapheme member, a heatpipe, or the like, or formed of magnesium, or the like, for example, andis a structure having a single member configuration formed bydie-casting or the like, for example, that is, a structure formed by asingle member. Particularly, in a case where the casing portion 88 isformed of aluminum, titanium, copper, stainless steel, a graphememember, a heat pipe, or the like, the casing portion 88 has high thermalconductivity. In addition, by causing at least a portion to become thethermal conductive member 88 h to be formed of metal, afiller-containing resin, a grapheme member, a heat pipe, or the like,the casing portion 88 may have high terminal conductivity. Here, asdescribed above, the casing portion 88 of the integrated shape includesa plate-shaped portion 88 p which is a flat plate-shaped portion, aframe-shaped portion 88 f which is a frame structure-shaped portion, andprotrusion members (fitting portions) 88 u and 88 v which areprotrusion-shaped portions.

The plate-shaped portion 88 p forms a rectangular flat plate-shapedportion that forms a surface-shaped portion on a rear side in the casingportion 88, and is adhered to the rear surface of the image displaydevice 80 to support and fix the image display device 80. That is, theplate-shaped portion 88 p also functions as a video device positioningportion that causes the rear surface SSr (referred to as a first edgesurface SS1) of the silicon substrate SS of the image display device 80to come into contact with the plate-shaped portion 88 p to determine anaccommodation position of the image display device 80.

The frame-shaped portion 88 f forms an edge portion of a U-shape inwhich a side (in the +y direction) where the image display device 80 isinserted in assembly is opened, on a peripheral side of the plate-shapedportion 88 p in the casing portion 88, and supports and fixes the imagedisplay device 80 by being adhered to the side surfaces of the imagedisplay device 80, that is, the side surfaces (second and third edgesurfaces SS2 and SS3) of the silicon substrate SS. That is, theframe-shaped portion 88 f also functions as a video device positioningportion that determines an accommodation position of the image displaydevice 80 by bringing the silicon substrate SS of the image displaydevice 80 into contact with the frame-shaped portion 88 f.

The protrusion members (fitting portions) 88 u and 88 v are attachmentportions for attachment alignment with respect to the lens barrel 39(see FIG. 3, or the like).

It may be considered that the casing portion 88 has a thermal conductivemember 88 h that conducts heat generated in the image display device 80by being in contact with a part of the image display device 80, and adisplay device positioning portion (video device positioning portion) 88t that performs positioning and fixing of the image display device 80.As described above, in a case where the casing portion 88 is formed of asingle metallic member, thermal conductivity becomes high in theentirety of the plate-shaped portion 88 p, the frame-shaped portion 88 fand the protrusion members (fitting portions) 88 u and 88 v, and theseportions may function as the thermal conductive member 88 h.Particularly, in the example shown in the figure, since the surfaceportions of the plate-shaped portion 88 p and the frame-shaped portion88 f are in direct contact with the image display device 80 to conductheat of the light emitting portion, it can be said that the plate-shapedportion 88 p and the frame-shaped portion 88 f function as main portionsof the thermal conductive member 88 h. Here, it is considered that theplate-shaped portion 88 p has a relatively large contact place with theimage display device 80 and greatly contributes to conduction (heatdissipation) of heat generated in the image display device 80. Theprotrusion members 88 u and 88 v may function as the thermal conductivemember 88 h by further conducting heat from the plate-shaped portion 88p and the frame-shaped portion 88 f.

Further, in the casing portion 88, a part of the surface portions of theplate-shaped portion 88 p and the frame-shaped portion 88 f alsofunctions as the display device positioning portion (video devicepositioning portion) 88 t that performs positioning by being in contactwith the image display device 80. Specifically, as shown in FIGS. 13Aand 13C, in the surface portions of the plate-shaped portion 88 p andthe frame-shaped portion 88 f, a first reference surface SF1 (planeperpendicular in the z direction) which is a reference plane portion forpositioning in the z direction, a second reference surface SF2 (planeperpendicular in the x direction) which is a reference plane portion forpositioning in the x direction, and a third reference surface SF3 (planeperpendicular in the y direction) which is a reference plane portion forpositioning in the y direction forms the display device positioningportion 88 t. The reference surfaces SF1 to SF3 come into contact withthe first edge surface SS1 which is the rear surface SSr among the edgesurfaces of the silicon substrate SS of a rectangular plate shape, andthe second and third edge surfaces SS2 and SS3 which are side surfacesformed on lateral sides of the edge surface SS1, to thereby performpositioning with high accuracy.

As described above, the casing portion 88 is a member that forms thedisplay device unit DU by supporting and fixing the image display device80 while positioning the image display device 80 through fitting andadhesion and accommodating the image display device 80 to be unitized(modularized) and forms an alignment portion for performing assembly ofthe image display device 80, that is, the display device unit DU withrespect to the lens barrel 39. Specifically, the casing portion 88includes a pair of protrusion members (fitting portions) 88 u and 88 u,and a pair of protrusion members (fitting portions) 88 v and 88 v as thealignment portion.

As shown in FIGS. 13A to 13C, with respect to the protrusion members 88u, 88 u, 88 v, and 88 v, the pair of protrusion members 88 v and 88 vwhich is provided on a side (in the +y direction) where the imagedisplay device 80 is inserted in assembly of the image display device 80and the casing portion 88 has a longitudinally long (long in the ydirection and short in the x direction) cross-sectional shape, comparedwith the other pair of protrusion members 88 u and 88 u which isprovided on a striking side with respect to the image display device 80.Thus, it is possible to assemble the image display device 80 whilemaking the casing portion 88 small as much as possible.

Furthermore, the protrusion members 88 u and 88 v which are fittingportions for fitting with another optical member (lens barrel 39) aresmoothly fitted to a rear end portion of the lens barrel 39 of theprojection lens (projection optical system) 30 so that the rear endportion is pinched therebetween, to thereby fix the casing portion 88 tothe lens barrel 39. In this case, an adhesive fills a space between theinner surfaces of the protrusion members (fitting portions) 88 u and 88v and side surfaces of the lens barrel 39. The adhesive is cured afteralignment of the casing portion 88 with respect to the lens barrel 39,so that the casing portion 88 is fixed to the lens barrel 39. Thus, itis possible to perform alignment relating to rotating shafts in threedirections in addition to three directions of an up-down direction, aright-left direction, and a front-rear direction. At a previous stage ofthe alignment, in the light guide member 10 of the light guide device20, a base side thereof is fitted to the lens barrel 39 to be fixedthereto. In this state, the casing portion 88 that accommodates theimage display device 80 as described above aligns with the lens barrel39 assembled with the light guide member 10 and the like, so thatpositioning of a final image can be performed. Particularly, in the caseof a right-left pair configuration as in this embodiment, it isnecessary to perform adjustment in the unit of pixels so that an imagefor the right eye side and an image for the left side eye are viewed ina state of being overlapped, and the positioning becomes very important.On the other hand, in this embodiment, since the image display device 80is fitted to the casing portion 88 with high accuracy, it is possible tominimize a margin for the adjustment, and to avoid increase in size ofthe device as much as possible while enabling positional adjustment.

Here, in addition to the above description, it may be considered that astructure for dissipating heat generated inside the image display device80 itself is provided. For example, in the image display device 80having the above-described structure, the FPC portion 80 f may beconfigured to include a thermal conductive material for conducting heatof the light emitting portion 80 k so that heat dissipation can beperformed through the FPC portion 80 f. That is, the FPC portion 80 fthat extends from the main body portion 80 a of the image display device80 may also function as a thermal conductive portion.

Hereinafter, an example (FIGS. 15A and 15B) of a manufacturing processof the display device unit DU, which is also a process of amanufacturing process of the virtual image display apparatus 100, and anexample (FIGS. 15C to 15E) of an assembly process of the display deviceunit DU and the lens barrel 39 will be described with reference to FIGS.15A to 15E. In FIGS. 15A and 15B, for ease of description, the displaydevice unit DU is shown in sectional side views, and in FIGS. 15C to15E, the display device unit DU is shown in side views.

First, as shown in FIG. 15A, in the plate-shaped portion 88 p and theframe-shaped portion 88 f of the casing portion 88, an adhesive 88 s tobecome a thermal conductive adhesion portion BD is applied on the firstto third reference surfaces SF1 to SF3 which become positioningreferences in the respective z, y and x directions (adhesive applyingprocess). As the adhesive 88 s, as described above, for example, a highthermal conductive silicon-based adhesive or a thermal conductive epoxyadhesive may be used. By using the high thermal conductive adhesive, itis possible to enhance heat dissipation even on a side where video lightis emitted.

Then, as indicated by an arrow A1 in FIG. 15B, the image display device80 is inserted from the +y side opened in the frame-shaped portion 88 fof a U-shape that forms the casing portion 88, and the respective edgesurfaces SS1 to SS3 of the silicon substrate SS of the image displaydevice 80 are brought into contact with the reference surfaces SF1 toSF3 on which the adhesive 88 s is applied, to thereby performpositioning (positioning process). Then, the adhesive 88 s is cured foradhesion and fixing (adhesion and fixing process). Through theseprocesses, the display device unit DU is manufactured (display deviceunit manufacturing process).

Then, as shown in FIG. 15C, in addition to the manufactured displaydevice unit DU, the lens barrel 39 which is a target to be assembledwith the display device unit DU is prepared (preparation process). Forexample, the lens barrel 39 is fixed, and the casing portion 88 isattached to jigs (not shown) so as to perform position adjustment withrespect to the lens barrel 39 in 6-axial directions. Further, anadhesive AH fills each groove portion 39 w which is a connection portionwith respect to the protrusion members (fitting portions) 88 u and 88 vof the casing portion 88, in the lens barrel 39. As shown in FIG. 15D,alignment (6-axial alignment) relating to rotational shafts in threedirections in addition to three directions of an up-down direction, aright-left direction, and a front-rear direction while appropriatelymoving the casing portion 88 from this state to insert the respectiveprotrusion members 88 u and 88 v corresponding to the groove portions 39w filled with the adhesive AH (alignment process). Finally, for example,in a state where waste at places for assembly or bonding with otherparts, or in the vicinity thereof is removed as necessary, as shown inFIG. 15E, a gap between the casing portion 88 and the lens barrel 39 issealed using a seal member SL of a tape shape (sealing process). Here,for example, the seal member SL may be configured to have high thermalconductivity (the seal member SL may be formed of a high thermalconductive material). Furthermore, in the case of the manufacturingdescribed above, the protrusion members 88 u and 88 v which areconnection portions with respect to another optical member (lens barrel39) in the casing portion 88 may function as the thermal conductivemember 88 h, to thereby transfer heat toward the other optical memberside through the protrusion members 88 u and 88 v (a specific examplewill be described with reference to FIGS. 17A to 17C, or the like).

As described above, since the virtual image display apparatus 100 thatincludes the display device unit DU according to this embodiment, theimage display device 80 which is a video device is a self-luminous typedevice that includes the light emitting portion 80 k that generatesvideo light and does not need a separate light source, it is possible toachieve weight reduction and miniaturization of the entirety of thevirtual image display apparatus 100. In addition, since the casingportion 88 of the display device unit DU includes the thermal conductivemember 88 h that conducts heat of the light emitting portion 80 k beingin contact with the image display device 80, it is possible to reduceincrease in internal temperature of the image display device 80.Further, although the image display device 80 is a self-luminous type,and particularly, includes an organic EL (OLED) element, it is possibleto avoid performance degradation or life shortening due to increase ininternal temperature, and to achieve excellent image formation.Furthermore, in manufacturing of the display device unit DU, it ispossible to perform easy and reliable assembly while securing a highheat dissipation characteristic. Here, particularly, using thecharacteristics of the silicon substrate SS, it is possible to performpositioning with high accuracy.

Third Embodiment

Hereinafter, a virtual image display apparatus according to a thirdembodiment will be described with reference to FIG. 16. The virtualimage display apparatus according to the third embodiment is formed bymodifying a part of the virtual image display apparatus according to thesecond embodiment. FIG. 16 is a diagram corresponding to FIG. 13A andillustrating an example of a display device unit DU assembled in thevirtual image display apparatus according to this embodiment. Further,since portions which are not particularly described are the same as inthe second embodiment, the entirety of the virtual image displayapparatus will not be shown and description thereof will not berepeated.

As shown in FIG. 16, the display device unit DU assembled in the virtualimage display apparatus according to this embodiment further includes amask portion 188 m that is provided on a side where video light isemitted, which is opposite to a thermal conductive member 88 h or adisplay device positioning portion 88 t that forms the casing portion88, and removes unnecessary light from component light emitted from theimage display device 80. In other words, a configuration in which alight shielding mask is added to the casing portion 88 is provided. Inthe case of the casing portion 88 having the configuration illustratedin the second embodiment, a structure in which a rear surface side (backsurface side) of the image display device 80 is covered with aplate-shaped portion 88 p is provided. Thus, in the casing portion 88,it may be difficult to realize a single component including a maskstructure on a display side in manufacturing. Accordingly, in thisembodiment, a configuration in which a mask portion 188 m which is alight shielding mask is further provided as a separate member isprovided.

The mask portion 188 m has a main body portion MK1 which has a framebody shape made of metal, for example, and protrusion portions MK2 whichprotrude from a part of the main body portion MK1 and perform alignment(positioning) with the casing portion 88. The mask portion 188 m ispositioned with respect to the casing portion 88 in the protrusionportions MK2, so that an opening OP1 formed in the main body portion MK1is disposed at an appropriate position, to thereby remove (shield)unnecessary light while emitting video light through the opening OP1.

On the other hand, the casing portion 88 has light shielding positioningportions (mask positioning portions) MKa provided corresponding to theprotrusion portions MK2 to accurately perform the positioning of themask portion 188 m. For example, grooves corresponding to the shapes andpositions of the protrusion portions MK2 in surface portions of theframe-shaped portion 88 f may be formed to function as the lightshielding positioning portions MKa that determine the position of themask portion 188 m by bringing the mask portion 188 m in contact withthe casing portion 88. By using the protrusion portions MK2 and thelight shielding positioning portions MKa, it is possible to performattachment with high accuracy.

Further, instead of the mask portion 188 m having the above-describedconfiguration, a configuration in which a separate light shielding tapeor light shielding sheet is fixed to the casing portion 88 forpositioning may be considered. In this case, the light shielding sheetor the like may be fixed using an adhesive, or may be fixed using adouble sided tape, for example.

Fourth Embodiment

Hereinafter, a virtual image display apparatus according to a fourthembodiment will be described with reference to FIGS. 17A to 17C. Thevirtual image display apparatus according to the fourth embodiment isformed by modifying a part of the virtual image display apparatusaccording to the second embodiment. A display device unit DU and a lensbarrel 39 (or an optical display unit LU) to be assembled in the virtualimage display apparatus according to this embodiment, of which anexample is shown in FIG. 17A and the like, correspond to a modificationexample of the display device unit DU and the lens barrel 39 that formthe virtual image display apparatus 100 in the second embodiment.Further, since portions which are not particularly described are thesame as in the second embodiment, the entirety of the virtual imagedisplay apparatus will not be shown and description thereof will not berepeated.

As shown in FIGS. 17A to 17C, the display device unit DU assembled inthe virtual image display apparatus according to this embodiment is incontact with the lens barrel 39 (or the optical display unit LU) in alarger number of places. Thus, it is possible to enable thermalconduction to the lens barrel 39, and to enhance a heat dissipationeffect.

Particularly, in the shown example, with respect to protrusion members(fitting portions), in addition to a pair of protrusion members 88 u and88 u and a pair of protrusion members 88 v and 88 v, a pair ofprotrusion members 88 x and 88 x is further provided between the pair ofprotrusion members 88 u and 88 u and the pair of protrusion members 88 vand 88 v, and a high thermal conductive adhesive such as a high thermalconductive silicon-based adhesive or a thermal conductive epoxy adhesiveis applied as an adhesive AH in each position. Thus, it is possible toperform assembly with the lens barrel 39 in a state where thermalconduction is enhanced.

Various modification examples may be considered in addition to theabove-described embodiments. For example, as in a display device unit DUof a modification example shown in FIGS. 18A and 18B, a configuration inwhich a fin structure FS is provided on a rear surface (back surface) ofthe plate-shaped portion 88 p that functions as the thermal conductivemember 88 h in the casing portion 88 may be used. Here, as shown in thefigures, plural fins FN are provided in the fin structure FS to formflow paths along an up-down direction (y direction) A2. If air is heatedin the vicinity of the display device unit DU, the air is expanded tobecome light, and moves up. Then, new air flows in from a lower side. Inthis case, if the plural fins FN are provided to have theabove-described shape, it is considered that convection current iseasily generated and heat exchange efficiency is enhanced. Further, forexample, the display device unit DU may be combined with anothercomponent while providing the flow paths along the up-down direction (ydirection) as described above. Furthermore, in addition to theabove-described structure in which the fins are provided, aconfiguration in which a separate heat dissipating structure isprovided, in other words, the heat dissipating structure is combined maybe used.

FIG. 19 is a conceptual diagram illustrating another modificationexample of a virtual image display apparatus. A virtual image displayapparatus 200 shown in FIG. 19 includes display device units DU and DUthat include a pair of left and right image display device 80 and 80,and a harness member HP which is a cable portion provided along a frameportion 102 that supports a pair of right and left light guide devices20 and 20 that respectively guides video light from display device unitsDU. In FIG. 19, FPC portions 80 f and 80 f that form the image displaydevices 80 and 80 are configured to be accommodated in cover-shapedexterior members 105 d (see FIG. 1) together with respective portionssuch as a circuit board, a connection portion, or the like to be folded,for example, over portions from the image display devices 80 and 80 tothe lens barrels 39 and 39.

For example, as shown in FIG. 1, the harness member HP is a cableportion that extends from one of the display devices 100A and 100B(extends from the display device 100B in FIG. 1), is connected to acontrol device or the like provided outside, and transmits a videosignal from the control device to the pair of right and left displaydevices 100A and 100B. Further, inside the device, for example, asconceptually shown in FIG. 19, the harness member HP includes cables CAand CB which are divided toward the first display device 100A and thesecond display device 100B, and are connected to the image displaydevices 80 and 80 that respectively form the display devices 100A and100B. The cables CA and CB are respectively connected to the FPCportions 80 f and 80 f of the image display devices 80 and 80, orconnection circuits or the like provided in end portions thereof. Thatis, the cables CA and CB extend to be connected to the display devices100A and 100B which are a pair of display portions. Here, the cable CAthat extends toward the first display device 100A is provided along ametallic frame portion 102, and is in contact with the frame portion102. With respect to the cables CA and CB that form the harness memberHP, various materials, shapes, and dispositions may be considered, buthere, as an example, the cables CA and CB have flat shapes, and aresealed by a copper foil tape, for example. With such a configuration, itis possible to provide high thermal conductivity to the cables CA andCB. Thus, for example, it is possible to dissipate heat from the FPCportions 80 f and 80 f over the entirety of the frame portion 102through the harness member HP. In addition, for example, as shown in thefigure, the cables CA and CB may be disposed to be directly in contactwith the image display devices 80 (display device units DU), to therebyassist heat dissipation. Furthermore, as described above, in a casewhere the harness member HP is sealed by a copper foil tape or the like,it may be considered that only a part of the harness member HP isconfigured by the copper foil tape or the like. Specifically, forexample, a configuration in which the harness member HP is configured bythe above-mentioned copper foil tape or the like on the inside of thedisplay devices 100A and 100B or in the vicinity thereof in the harnessmember HP that extends from a controller (not shown) which is a controldevice or the like provided outside may be considered. Thus, it ispossible to prevent heat generated in the controller from beingtransferred from the harness member HP. Further, in a case where theharness member HP is entirely configured by sealing using a copper foilor the like up to a place including the controller, a member having lowthermal conductivity such as an insulating film may be provided betweenthe controller and the display devices 100A and 100B, in the harness HP,to block heat from the controller. Furthermore, for example, variousforms may be considered with respect to interconnects of the cables CAand CB that form the harness member HP. Specifically, in the exampleshown in FIG. 19, a configuration in which each of the cables CA and CBare divided from a portion before connection to a corresponding one ofthe display devices 100A and 100B is shown, but instead, for example, aconfiguration in which a single cable extends up to the inside of oneimage display device 80 among the pair of right and left image displaydevices 80 and 80 without being divided into two and is divided into twoinside the one image display device 80 and one of the two divided cablesextends toward the other image display device 80 may be considered.

FIG. 20 is a diagram illustrating still another modification example ofa virtual image display apparatus. In a virtual image display apparatus300 shown in FIG. 20, an outside air flow path forming portion HL thatforms a flow path for causing outside air to flow through a displaydevice unit DU. More specifically, as shown in the figure, the outsideair flow path forming portion HL includes an air hole FH provided on afront side of an exterior member 105 d that accommodates the displaydevice unit DU, and an air hole BH provided on a rear side thereof, inwhich a flow path is formed so that outside air AR flows from the airhole FH to the air hole BH. With respect to the outside air flow pathforming portion HL, in addition to the shown example, various forms maybe considered in consideration of suppression of generation of straylight, entrance of dust, or the like. As described above, by providingthe outside air flow path forming portion HL so that outside air flowstherethrough, it is possible to promote heat dissipation. Further, whena structure for flow-through of outside air as described above isprovided, a water-proof structure may be separately provided asnecessary. For example, a configuration in which a filter member (PTFEfilter, or the like) through which air passes but water does not pass isprovided in each of the air holes FH and BH which are ports of the flowpath, or for example, a configuration in which a member or the like thatforms an optical display unit LU is sealed in a space separated from theflow path for waterproof may be considered.

In addition, as a modification example, when a heat dissipating portionDP is provided as in a virtual image display apparatus 400 of which aninner structure is conceptually shown in FIGS. 21A and 21B, a noisecountermeasure sheet NP may be provided. FIG. 21A is a conceptual planview of the virtual image display apparatus 400, and FIG. 21B is aconceptual side view of the virtual image display apparatus 400. Thevirtual image display apparatus 400 includes the heat dissipatingportion DP that extends from a rear surface side (back surface side) ofan image display device 80 to a frame portion 102. That is, the heatdissipating portion DP functions as a thermal conductive member thatdissipates heat. In a case where such a heat dissipating portion DP isprovided, there is a concern that electromagnetic waves may be generateddue to weak power or the like on a circuit board or the like of anorganic EL panel that forms the image display device 80 and theelectromagnetic waves may be changed to noise through the heatdissipating portion DP and may be transferred to other members to affectthe other members. In order to prevent such a situation, herein, asshown in the figure, a configuration in which the noise countermeasuresheet NP is provided between the image display device 80 and the heatdissipating portion DP is used. As the noise countermeasure sheet NP,for example, a member such as an electromagnetic wave absorbing sheetmade of a mixture of silicon polymer, magnetic metal power, and ceramicsmay be applied. In this case, it is possible to provide the noisecountermeasure sheet NP with low thermal conductivity while securingthermal conductivity. As described above, by providing the noisecountermeasure sheet NP, noise of an organic EL panel formed on asilicon substrate in the image display device 80 flows toward the frameportion 102 through the silicon substrate and the heat dissipatingportion DP (for example, thermal conductive sheet), and thus, it ispossible to prevent the noise from being transferred to a circuit boardor the like of each of the display devices 100A and 100B, for example.Further, for example, the heat dissipating portion DP may be formed of amember having excellent thermal conductivity and electromagnetic waveabsorption. Instead of the case shown in FIGS. 21A and 21B, for example,as shown in FIG. 22, a configuration in which a pair of frame portions102 are provided so that two components of a first portion 102 x and asecond portion 102 y are divided at a portion where left and right lightguide members are retained and the noise countermeasure sheet NP isprovided therebetween, to thereby prevent noise of the right and leftdisplay devices from being conducted, may be considered. Furthermore, aconfiguration in which a portion close to a circuit board, a flexiblecable, or the like is covered with a noise countermeasure sheet (memberhaving a low electrical conductivity) may be considered.

Others

The invention has been described with reference to the above-describedembodiments, but the invention is not limited to the embodiments, andvarious modifications may be made in a range without departing from theconcept of the invention.

In the above description, for example, the adhesive 88 s to become thehigh thermal conductive adhesion portion BD, which is applied on therespective reference surfaces SF1 to SF3, is entirely over the contactplaces, but the adhesive 88 s may be partially applied. Thus, forexample, in the respective reference surfaces SF1 to SF3, places thatare directly in contact with corresponding edge surfaces SS1 To SS3without through the high thermal conductive adhesion portion BD may bepresent, to thereby achieve thermal conductivity. Further, aconfiguration in which the thermal conductive member 88 h of the casingportion 88 is in contact with a part of, instead of the entirety of, theedge surfaces SS1 to SS3 of the silicon substrate SS using high thermalconductivity of the silicon substrate SS may be used.

In the above description, for example, in FIGS. 18A and 18B, the finstructure is provided, but the invention is not limited thereto. Forexample, the fin structure may be applied to other embodiments. Further,for example, various structures or means in which a cooling fan orPeltier element is provided may be used.

Further, other members that are directly or indirectly connected to thedisplay device unit DU to perform thermal conduction, such as the lensbarrel 39 or the like, may be formed of a metallic material, afiller-containing resin, a grapheme member, a heat pipe, or the like,for example.

In the above description, the element substrate of the image displaydevice 80 is a silicon substrate, but other members such as quartz glassmay be used as long as necessary heat dissipation and position accuracycan be secured.

In the above description, the casing portion 88 is formed of a metallicmaterial having high thermal conductivity, but other materials (forexample, a resin material) may be used (partially used) as long as heatdissipation or accommodation position accuracy of the image displaydevice 80 can be secured.

In the above description, various devices may be used as the imagedisplay device 80, and for example, a configuration using a reflectiontype liquid crystal display device may be used, and a digitalmicro-mirror device or the like, instead of a video display device thatincludes a liquid crystal display device or the like, may be used.

In the above description, the half mirror layer of the second surfaceS12 is formed of a metallic reflecting film or a dielectric multi-layerfilm, but may be replaced with a flat or curved hologram element.Further, the fifth surface S15 may be formed using a hologram elementinstead of a mirror reflecting surface.

In the above description, the light guide members 10 or the like extendin a transverse direction where the eyes are arranged, but the lightguide member 10 may be disposed to extend in a longitudinal direction.In this case, the light guide members 10 has a structure in which thelight guide members 10 are not arranged in series but are arranged inparallel.

In the above description, only a form in which image light and externalworld light overlap is shown, but a virtual image display apparatus inwhich an image form based on image light and an image form based onexternal world light can be observed in a switchable manner withoutoverlapping may be used.

The technique of the invention may be applied to a so-called videosee-through product configured by a display and an imaging device.

The technique of the invention, that is, a casing (video device unitstructure) having a structure for heat dissipation in unitization of animage display device (video device) may be used in a display device suchas a camera finder or a small projector.

In the case of the other applications described above, for example, in acase where it is not necessary to perform high accuracy alignment withother optical parts with respect to a display device unit (video deviceunit), a configuration in which attachment portions (typically,protrusion members (fitting portions) 88 u and 88 v) for the alignmentis not provided may be used.

The entire disclosure of Japanese Patent Application No.: 2016-025615,filed Feb. 15, 2016 and 2016-192990, filed Sep. 30, 2016 are expresslyincorporated by reference herein.

What is claimed is:
 1. A head mounted display comprising: a firstdisplay device includes a first video device, a first casing portion, afirst projection optical system, a first frame portion, a first lightguide member, and a first thermal conductive tape; a second displaydevice includes a second video device, a second casing portion, a secondprojection optical system, a second frame portion, a second light guidemember, and a second thermal conductive tape, wherein the first videodevice emits first video light from a light emitting surface of thefirst video device to the first projection optical system, the secondvideo device emits second video light from a light emitting surface ofthe second video device to the second projection optical system, thefirst projection optical system emits the first video light from thefirst video device to the first light guide member, the secondprojection optical system emits the second video light from the secondvideo device to the second light guide member, the first casing portionaccommodates the first video device and exposes an opposite surface ofthe first video device, the opposite surface of the first video deviceis a surface opposite to the light emitting surface of the first videolight, the second casing portion accommodates the second video deviceand exposes an opposite surface of the second video device, the oppositesurface of the second video device is a surface opposite to the lightemitting surface of the second video light, the first thermal conductivetape attached both of the opposite surface of the first video device anda surface of the first frame portion that is not parallel with thesurface of the first frame portion, the second thermal conductive tapeattached both of the opposite surface of the second video device and asurface of the second frame portion that is not parallel with thesurface of the first frame portion.
 2. The head mounted displayaccording to claim 1, wherein the first video device includes an OLEDelement on a first silicon substrate, the second video device includesan OLED element on a second silicon substrate, the opposite surface ofthe first video device is a surface of the first silicon substrate, andthe opposite surface of the second video device is a surface of thesecond silicon substrate.
 3. The head mounted display according to claim2, wherein the first video device contacts with the first casing portionat edge surfaces of the first silicon substrate, and the second videodevice contacts with the second casing portion at edge surfaces of thesecond silicon substrate.
 4. The head mounted display according to claim1, wherein the first casing portion includes a first video devicepositioning portion that contacts with a place other than the oppositesurface of the first video device, and the second casing portionincludes a second video device positioning portion that contacts with aplace other than the opposite surface of the second video device.
 5. Thehead mounted display according to claim 1, wherein the first videodevice includes a first flexible printed circuit portion that is notoverlapped with the first thermal conductive tape, the second videodevice includes a second flexible printed circuit portion that is notoverlapped with the second thermal conductive tape.
 6. The head mounteddisplay according to claim 5, wherein the first flexible printed circuitportion includes a thermal conductive material, and the second flexibleprinted circuit portion includes a thermal conductive material.